LinkSwitch®-XT Family Energy Efficient, Low Power Off-Line Switcher IC

Description

LinkSwitch-XTincorporates a 700 V power MOSFET, oscillator, simple ON/OFF control scheme, a high-voltage switched current source, frequency jittering, cycle-by-cycle current limit and

thermal shutdown circuitry onto a monolithic IC. The startup and operating power are derived directly from the DRAIN pin, eliminating the need for a bias winding and associated circuitry.

Product Highlights

Optimized for Lowest System Cost

• Proprietary IC trimming and transformer construction techniques enable Clampless™ designs with LNK362 for lower system cost, component count and higher efficiency

• Fully integrated auto-restart for short circuit and open loop protection

• Self-biased supply – saves transformer auxiliary winding and associated bias supply components

• Frequency jittering greatly reduces EMI

• Meets HV creepage requirements between DRAIN and all other pins both on the PCB and at the package

• Lowest component count switcher solution

Features Superior to Linear/RCC

• Accurate hysteretic thermal shutdown protection – automatic recovery improves field reliability

• Universal input range allows worldwide operation

• Simple ON/OFF control, no loop compensation needed

• Eliminates bias winding – simpler, lower cost transformer

• Very low component count – higher reliability and single side printed circuit board

• Auto-restart reduces delivered power by 95 during short circuit and open loop fault conditions

• High bandwidth provides fast turn-on with no overshoot and excellent transient load response

EcoSmart®

– Extremely Energy-Efficient

• Easily meets all global energy efficiency regulations with no added components

• No-load consumption <300 mW without bias winding at 265 VAC input (<50 mW with bias winding)

• ON/OFF control provides constant efficiency to very light loads – ideal for mandatory CEC regulations

Applications

• Chargers/adapters for cell/cordless phones, PDAs, digital cameras, MP3/portable audio players, and shavers

• Supplies for appliances, industrial systems, and metering